Pat Guerin, Citigroup’s global head of sales and divestitures and a veteran London investment banker, has left to join Jefferies’ New York office.

Guerin, who spent over ten years at UBS, latterly as joint head of its M&A business for EMEA, left Citi in September after three years in his current role, according to sources close to the situation, and joined Jefferies later in the month as a managing director.

He joined Citigroup in 2011 from UBS as part of the US bank’s plans to bolster its senior investment banking ranks in the wake of a string of departures. Guerin had been with UBS since 2004.

This year, Citigroup has been actively building its equities team, latterly bringing in Claudio Villa as managing director, head of capital markets for Italy. It’s also been adding to its equities trading team, but has nonetheless seen a string of senior departures over the past 12 months including Andy Thomson, head of its equities business, who left in July to “spend more time with his family”, and Nick Rowe, its head of prime finance.

However, the bank has also lost a number of senior figures in its advisory business in recent months. Nick Tansley, a managing director in its global industrials group, left to join Blackstone in July following on from the departure of Dimitris Georgiou, the co-head of the division, who joined RBC Capital Markets. Paul Tomasic, who headed Citigroup’s healthcare team in EMEA, also joined RBC.

Jefferies, meanwhile, revealed some stellar third quarter results in September – announcing record revenues of $835m – and said that it would be adding headcount “particularly to drive the growth of investment banking and selectively on the trading side”.